Source: U.S. military assessing options for humanitarian aid in Libya

It's difficult to find "anyone or any organization" that can discuss post-conflict planning

Any U.S. assistance is likely to take place in a broader NATO effort under the U.N umbrella

Washington (CNN) -- The U.S. military is looking at options for both delivering humanitarian assistance into Libya and helping with the return of refugees, CNN learned Thursday.

A senior U.S. military official with direct knowledge of the effort emphasized there have been no requests for assistance, but the military is doing "prudent planning" so it is ready if requested.

President Barack Obama's policy of ruling out any U.S. troops on the ground remains in effect, the official said, but military authorities also have indicated there is the potential for military aircraft and ships delivering aid to airfields and ports -- which could/would involve U.S. military on the ground in Libya.

The senior U.S. military official said the U.S. is "really pressing to see what, if any, U.S. military support may be required in Libya." But the official said it's very difficult right now to find "anyone or any organization" that can address "post-conflict planning."

The National Transitional Council, which will function as an interim government. is not offering much detail about what it wants or needs yet.

Any U.S. assistance is likely to take place within a broader post-conflict NATO effort under a United Nations umbrella, a senior NATO official told CNN.

NATO military officials are now beginning initial planning efforts in order to be ready if they are asked for help. That includes planning for humanitarian aid, air and maritime security, and even the possibility of training Libyan military forces at locations outside the country.

Arab allies such as Qatar and Jordan, and perhaps others, are expected to join in any post-conflict effort to keep it from looking like NATO nations are running the show, the official said.